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The ‘Z’ stars are a mouthful!

On early evenings in June, just after twilight, look for a moderately bright star in the low Butler southeast sky a little above the horizon. It has a decidedly ruddy hue to it. That’s Antares, the brightest star of the summer constellation Scorpius the Scorpion.

It’s one of the few constellations that really looks like what it’s supposed to be. In the early evening, you can only see the three almost vertically orientated, moderately bright stars in a nearly straight line just above Antares that outlines the scorpion’s head. Antares marks the heart of the beast.

To see the tail and stinger of the celestial scorpion, you have to wait until well after 11 p.m. By then, all of Scorpius will be high enough above the southern horizon.

Just to the upper right of the three stars that make up Scorpius' head is the faint constellation Libra the Scales.

Unlike Scorpius, it looks nothing like what it’s supposed to be. It allegedly outlines the classic Roman scales of justice.

Libra is made up of incredibly faint stars with two exceptions: Zubeneschamali, pronounced zuba-ne-sha-molly, and Zubenelgenubi, pronounced zoo-be-nel-jenew-bee. Try to say those mouthfuls over and over as fast as you can!

Spotting what I call the “Z stars” is much easier than pronouncing them. Look for two identically moderate bright stars to the right of the three stars of Scorpius’ head.

The stars will be orientated diagonally with Zubeneschamali on the upper left and Zubenelgenubi on the lower right. These tongue-twisting Arabic names translate into English as the south and north claws, respectively.

What do the "claw" stars have to do with the Roman scales of justice? Absolutely nothing! As it turns out, the Roman Emporer Julius Caesar invented the constellation Libra around the time of Christ.

Once upon a time, the Z stars of Libra were indeed the claws of the neighboring constellation Scorpius the Scorpion. One day, Caesar just decided to hack off the claws of Scorpius and made the "Z" stars, and a few others around them, into the new constellation Libra the Scales. Caesar had that kind of power!

Zubenelgenubi appears to the naked eye as a single star, but like many stars is actually a multiple-star system. It comprises three stars, all revolving around each other, 76 light-years away from Earth. If you’re new to this column, light-years are the easiest way to describe the incredible distance to stars. A light-year is defined as the distance a beam of light travels in one year, about 5.8 trillion miles. The three stars of Zubenelgenubi are nearly 440 trillion miles away!

Zubeneschamali is even farther away at 185 light-years distant. It’s a blue giant star well over 4 million miles in diameter. Our own sun isn’t even a million miles across. Its surface temperature is believed to be nearly 22,000 degrees, more than twice as hot as our sun.

Enjoy the two tongue-twisting stars of late spring-early summer. Don’t feel bad if you can’t pronounce them. I’ve been into stargazing for nearly 60 years and still stumble on them!

Celestial Happening this weekend: The very bright planet Venus and much fainter Mars are drawing closer and closer to each other in the low western sky toward the end of evening twilight. With just a pair of binoculars, you’ll see the distinctly orange-red-hued Mars, just to the upper left of the “Beehive” star cluster, nearly 600 light-years away!

Mike Lynch is an amateur astronomer and retired broadcast meteorologist for WCCO Radio in Minneapolis/St. Paul. He is the author of "Stars: a Month by Month Tour of the Constellations," published by Adventure Publications and available at bookstores and Contact him at

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